Resistance training devices and free weights are well known for the beneficial results in physical and weight training, and are found in many gymnasia and even in private homes. It is also well accepted that using a variety of exercise devices can assist in maintaining the interest of the user and in addition can provide alternate ways of using various muscle groups and enhance the balance between the capabilities of the various muscle groups.
Sleds operated either by pushing or by dragging through the use of a harness slide readily across soft surfaces such as carpets and grassy areas, but do not perform well on hard surfaces such as wood and concrete floors and may even cause significant damage to either the sled or the underlying surface.
Devices equipped with one or more wheels roll readily across many surfaces and, like sleds, can be fitted with a user-selected range of weights to provide the desired exercise level. Indeed, the common wheelbarrow is a form of such device, although it is rarely used purely for exercise purposes.
However, presently known exercise devices are not highly adaptable as they are not readily capable of operating alternatively with wheels, as a lifting device or as a sled.